Question

简便计算： 谁能解决下面的4道简便计算，15财富值！

0.049×7.8
3.97×5.06
3.5×4.28+1.75×11.44
4.386÷0.125÷8

Answer 1

0.049×7.8
=0.05×7.8-0.001×7.8
=0.39-0.0078
=0.3822

3.97×5.06
=4×5.06-0.03×5.06
=20.24-0.1518
=20.0882

3,5×4.28+1.75×11.44
=3.5×4.28+3.5×5.72
=3.5×(4.28+5.72)
=3.5×10
=35

4.386÷0.125÷8
=4.386÷(0.125×8)
=4.386×1
=4.386

Answer 2

最后一个4.386/（0.125*8）=4.386
倒数第二个1.75（2*4.28+1*11.44）=20*1.75=35